drm/exynos: hdmi: support extra resolutions using drm_display_mode timings

This patch programs the core and timing generator registers using the
timing data provided in drm_display_mode and not using hard-coded
configurations.

Additional PHY configs has been added. This allows us to support more
permissible resolutions and refresh rates.

Signed-off-by: Rahul Sharma <rahul.sharma@samsung.com>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Shirish S <s.shirish@samsung.com>
Signed-off-by: Akshay Saraswat <Akshay.s@samsung.com>
Signed-off-by: Inki Dae <inki.dae@samsung.com>